Membership is free and only requires you log onto the PSN once a day for approximately 12 minutes to make sure your games are all up to date, so that when you finally have time there is no wasted update downloading...
My PS4 has not been switched on for about a week and a half, my vita about a week. Starting a new job and and not having any time off makes me super tired so by the time I have stopped studding at 9:30/10 pm I don't feel like gaming.